feat(command-zone): add commander tax counter system with tests

Implement CommanderTaxCounter - tracks casting cost increases for
commanders that have been cast multiple times.

Key components:
- CommanderTaxCounter: specialized counter with value clamping
- AbstractCounter modifications: support for counter ID system
- CounterGeneral/TranslateCounterName: UI integration for display

Design decisions:
- Counter values clamped to valid range (0 to max)
- Builds on counter_ids.h constants from commit 1
- Uses z_values.h from commit 4 for proper visual layering
- Counter visibility tied to zone state (hidden when zone hidden)

Test coverage:
- commander_tax_counter_test: verifies setValue clamping behavior
- counter_visibility_test: verifies visibility state transitions

Note: Tests include <climits> for INT_MIN usage (required on some compilers
like GCC on Debian 11 where INT_MIN is not transitively included).

tests/command_zone/CMakeLists.txt

@@ -31,6 +31,22 @@ target_link_libraries(command_zone_logic_test
 
 add_test(NAME command_zone_logic_test COMMAND command_zone_logic_test)
 
+# ------------------------
+# Commander Tax Counter Test
+# Tests setValue clamping behavior
+# ------------------------
+add_executable(commander_tax_counter_test
+    commander_tax_counter_test.cpp
+)
+
+target_link_libraries(commander_tax_counter_test
+    PRIVATE Threads::Threads
+    PRIVATE ${GTEST_BOTH_LIBRARIES}
+    PRIVATE ${TEST_QT_MODULES}
+)
+
+add_test(NAME commander_tax_counter_test COMMAND commander_tax_counter_test)
+
 # ------------------------
 # Command Zone State Test
 # Tests the extracted CommandZoneState pure state machine
@@ -53,10 +69,28 @@ target_link_libraries(command_zone_state_test
 
 add_test(NAME command_zone_state_test COMMAND command_zone_state_test)
 
+# ------------------------
+# Counter Visibility Test
+# Tests counter visibility during zone state transitions
+# ------------------------
+add_executable(counter_visibility_test
+    counter_visibility_test.cpp
+)
+
+target_link_libraries(counter_visibility_test
+    PRIVATE Threads::Threads
+    PRIVATE ${GTEST_BOTH_LIBRARIES}
+    PRIVATE ${TEST_QT_MODULES}
+)
+
+add_test(NAME counter_visibility_test COMMAND counter_visibility_test)
+
 # ------------------------
 # Dependencies on gtest
 # ------------------------
 if(NOT GTEST_FOUND)
     add_dependencies(command_zone_logic_test gtest)
+    add_dependencies(commander_tax_counter_test gtest)
     add_dependencies(command_zone_state_test gtest)
+    add_dependencies(counter_visibility_test gtest)
 endif()